Alert archive / Minnesota / Tornado Watches in 2004

Tornado Watch 82

April 18, 200438 counties in Minnesota; 10 counties in Wisconsin

The Storm Prediction Center issued this tornado watch at Apr 18, 2004, 1:40 PM CDT for 38 counties in Minnesota; 10 counties in Wisconsin. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Apr 18, 2004, 1:40 PM CDT (18:40 UTC)
Expired
Apr 18, 2004, 8:00 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
All 48 counties

Aitkin County, MN, Anoka County, MN, Benton County, MN, Carlton County, MN, Carver County, MN, Chippewa County, MN, Chisago County, MN, Cook County, MN, Crow Wing County, MN, Douglas County, MN, Grant County, MN, Hennepin County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, Lac qui Parle County, MN, Lake County, MN, Lincoln County, MN, Lyon County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Otter Tail County, MN, Pine County, MN, Pope County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Sherburne County, MN, Stearns County, MN, Stevens County, MN, Swift County, MN, Todd County, MN, Wadena County, MN, Washington County, MN, Wright County, MN, Yellow Medicine County, MN, Ashland County, WI, Barron County, WI, Bayfield County, WI, Burnett County, WI, Douglas County, WI, Polk County, WI, Price County, WI, Rusk County, WI, Sawyer County, WI, Washburn County, WI

The radar

The Minneapolis radar (KMPX), 140 km from the middle of the area, began a volume at 18:39 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Warnings issued inside it

42 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 18, 3:24 PM CDTSevere Thunderstorm WarningMPXSherburne36 min
Apr 18, 3:27 PM CDTSevere Thunderstorm WarningMPXBenton, Mille Lacs, Morrison, Stearns63 min
Apr 18, 3:46 PM CDTSevere Thunderstorm WarningMPXIsanti, Kanabec59 min
Apr 18, 3:52 PM CDTTornado WarningMPXIsanti, Kanabec23 min
Apr 18, 3:54 PM CDTTornado WarningMPXIsanti, Kanabec21 min
Apr 18, 3:57 PM CDTSevere Thunderstorm WarningMPXSherburne33 min
Apr 18, 3:59 PM CDTTornado WarningDLHPine61 min
Apr 18, 4:00 PM CDTSevere Thunderstorm WarningMPXMeeker, Wright45 min
Apr 18, 4:08 PM CDTTornado WarningMPXSherburne37 min
Apr 18, 4:13 PM CDTSevere Thunderstorm WarningDLHLake, Saint Louis62 min
Apr 18, 4:15 PM CDTTornado WarningMPXKanabec30 min
Apr 18, 4:27 PM CDTTornado WarningMPXIsanti48 min
Apr 18, 4:41 PM CDTTornado WarningDLHBurnett64 min
Apr 18, 4:42 PM CDTSevere Thunderstorm WarningMPXChisago48 min
Apr 18, 4:56 PM CDTSevere Thunderstorm WarningMPXMeeker, Wright49 min
Apr 18, 5:13 PM CDTSevere Thunderstorm WarningDLHDouglas32 min
Apr 18, 5:15 PM CDTSevere Thunderstorm WarningMPXSherburne30 min
Apr 18, 5:17 PM CDTSevere Thunderstorm WarningMPXAnoka, Isanti58 min
Apr 18, 5:18 PM CDTSevere Thunderstorm WarningMPXBrown, Redwood42 min
Apr 18, 5:23 PM CDTTornado WarningDLHWashburn67 min
Apr 18, 5:34 PM CDTSevere Thunderstorm WarningMPXChisago, Isanti41 min
Apr 18, 5:44 PM CDTSevere Thunderstorm WarningFSDLincoln, Lyon46 min
Apr 18, 5:46 PM CDTSevere Thunderstorm WarningFSDLincoln, Lyon44 min
Apr 18, 5:46 PM CDTSevere Thunderstorm WarningMPXCarver, McLeod, Renville, Sibley59 min
Apr 18, 5:47 PM CDTSevere Thunderstorm WarningMPXWright43 min
Apr 18, 5:52 PM CDTSevere Thunderstorm WarningMPXSherburne38 min
Apr 18, 5:53 PM CDTSevere Thunderstorm WarningDLHLake52 min
Apr 18, 5:54 PM CDTTornado WarningDLHSawyer66 min
Apr 18, 5:58 PM CDTSevere Thunderstorm WarningMPXAnoka, Hennepin47 min
Apr 18, 5:59 PM CDTSevere Thunderstorm WarningMPXBrown, Nicollet, Redwood61 min
Apr 18, 6:02 PM CDTTornado WarningMPXBrown, Redwood43 min
Apr 18, 6:16 PM CDTSevere Thunderstorm WarningMPXChisago44 min
Apr 18, 6:22 PM CDTSevere Thunderstorm WarningMPXRamsey, Washington53 min
Apr 18, 6:30 PM CDTSevere Thunderstorm WarningFSDLyon30 min
Apr 18, 6:32 PM CDTSevere Thunderstorm WarningDLHAshland43 min
Apr 18, 6:34 PM CDTSevere Thunderstorm WarningMPXWright26 min
Apr 18, 6:42 PM CDTSevere Thunderstorm WarningMPXAnoka, Hennepin48 min
Apr 18, 6:50 PM CDTSevere Thunderstorm WarningMPXCarver, McLeod40 min
Apr 18, 7:02 PM CDTSevere Thunderstorm WarningMPXChisago43 min
Apr 18, 7:13 PM CDTSevere Thunderstorm WarningMPXRamsey, Washington47 min
Apr 18, 7:33 PM CDTSevere Thunderstorm WarningMPXCarver42 min
Apr 18, 7:43 PM CDTSevere Thunderstorm WarningMPXBarron, Polk, Rusk47 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 6.7 hours before the alert went out and 140 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2004-04-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 680 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2004-04-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 361 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
680 J/kg
Mixed-layer CIN
-274 J/kg
Mixed-layer LCL
697 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
361 m²/s²
0-3 km storm-relative helicity
401 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS20 KWNS 181839
SEL2  
SPC WW 181840
MNZ000-WIZ000-LSZ000-190100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 82
NWS STORM PREDICTION CENTER NORMAN OK
140 PM CDT SUN APR 18 2004

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       CENTRAL AND EASTERN MINNESOTA
       NORTHERN WISCONSIN
       LAKE SUPERIOR

EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 140 PM UNTIL 800
PM CDT.

...THIS IS A PARTICULARLY DANGEROUS SITUATION...

DESTRUCTIVE TORNADOES...LARGE HAIL TO 3 INCHES IN DIAMETER...
THUNDERSTORM WIND GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE
POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 80 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 65 MILES SOUTHWEST OF ALEXANDRIA MINNESOTA TO
90 MILES EAST OF DULUTH MINNESOTA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...CONTINUE...WW 81...

DISCUSSION...RAPID SEVERE THUNDERSTORM DEVELOPMENT EXPECTED TO OCCUR
THIS AFTERNOON ACROSS CENTRAL MN...SPREADING INTO NORTHERN WI THIS
EVENING.  DEEP SURFACE LOW...VERY STRONG LOW/MID LEVEL WIND
FIELDS...AND MODERATE INSTABILITY WILL ENHANCE THE THREAT OF
SUPERCELL STORMS CAPABLE OF VERY LARGE HAIL...DAMAGING WINDS...AND
TORNADOES.  POTENTIAL WILL EXIST FOR STRONG TORNADOES IMMEDIATELY
ALONG SURFACE WARM FRONT FROM CENTRAL MN INTO NORTHERN WI.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 25040.


...HART

462,0961 475,0901 453,0901 440,0961

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 17, 7:45 PM CDTSevere Thunderstorm WatchSPCBlue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 7 more5 hr
Apr 17, 9:31 PM CDTMesoscale DiscussionSPCBlue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 7 more119 min
Apr 17, 10:05 PM CDTTornado WatchSPCBlue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 7 more5 hr
Apr 17, 11:10 PM CDTMesoscale DiscussionSPCBig Stone, Chippewa, Cottonwood, Grant, Jackson, Kandiyohi and 14 more95 min
Apr 17, 11:35 PM CDTSevere Thunderstorm WatchSPCBig Stone, Brown, Chippewa, Cottonwood, Jackson, Kandiyohi and 16 more5 hr
Apr 17, 11:50 PM CDTMesoscale DiscussionSPCBlue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 7 more85 min
Apr 18, 12:30 AM CDTSevere Thunderstorm WatchSPCAnoka, Carver, Chisago, Dakota, Goodhue, Hennepin and 11 more5 hr
Apr 18, 2:37 AM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Big Stone, Brown, Carlton and 40 more53 min
Apr 18, 4:43 AM CDTMesoscale DiscussionSPCAitkin, Benton, Carlton, Cass, Chisago, Crow Wing and 15 more32 min
Apr 18, 8:04 AM CDTMesoscale DiscussionSPCAitkin, Benton, Carlton, Cass, Crow Wing, Douglas and 6 more86 min
Apr 18, 12:39 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Big Stone, Carlton, Carver and 32 more2 hr
Apr 18, 2:20 PM CDTSevere Thunderstorm WatchSPCLincoln, Lyon, Pipestone, Rock6 hr
Apr 18, 3:33 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Carlton, Chisago, Crow Wing and 12 more117 min
Apr 18, 4:15 PM CDTMesoscale DiscussionSPCBlue Earth, Brown, Cottonwood, Dodge, Faribault, Fillmore and 15 more60 min
Apr 18, 4:40 PM CDTTornado WatchSPCBlue Earth, Cottonwood, Dodge, Faribault, Freeborn, Jackson and 6 more5 hr
Apr 18, 5:23 PM CDTMesoscale DiscussionSPCLincoln, Lyon, Pipestone, Rock2 hr
Apr 18, 6:35 PM CDTTornado WatchSPCBrown, Carver, Dakota, Goodhue, Hennepin, Le Sueur and 7 more5 hr
Apr 18, 1:49 AM CDTMesoscale DiscussionSPCCalumet, Columbia, Dane, Dodge, Fond du Lac, Green and 11 more56 min

Nearby

Tornado Watches in Minnesota, 2004Tornado Watches in Wisconsin, 2004Every tornado watch in 2004

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.